/* * High Precisition Event Timer emulation * * Copyright (c) 2007 Alexander Graf * Copyright (c) 2008 IBM Corporation * * Authors: Beth Kon <bkon@us.ibm.com> * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, see <http://www.gnu.org/licenses/>. * * ***************************************************************** * * This driver attempts to emulate an HPET device in software. */ #include "hw.h" #include "pc.h" #include "console.h" #include "qemu-timer.h" #include "hpet_emul.h" //#define HPET_DEBUG #ifdef HPET_DEBUG #define DPRINTF printf #else #define DPRINTF(...) #endif static HPETState *hpet_statep; uint32_t hpet_in_legacy_mode(void) { if (hpet_statep) return hpet_statep->config & HPET_CFG_LEGACY; else return 0; } static uint32_t timer_int_route(struct HPETTimer *timer) { uint32_t route; route = (timer->config & HPET_TN_INT_ROUTE_MASK) >> HPET_TN_INT_ROUTE_SHIFT; return route; } static uint32_t hpet_enabled(void) { return hpet_statep->config & HPET_CFG_ENABLE; } static uint32_t timer_is_periodic(HPETTimer *t) { return t->config & HPET_TN_PERIODIC; } static uint32_t timer_enabled(HPETTimer *t) { return t->config & HPET_TN_ENABLE; } static uint32_t hpet_time_after(uint64_t a, uint64_t b) { return ((int32_t)(b) - (int32_t)(a) < 0); } static uint32_t hpet_time_after64(uint64_t a, uint64_t b) { return ((int64_t)(b) - (int64_t)(a) < 0); } static uint64_t ticks_to_ns(uint64_t value) { return (muldiv64(value, HPET_CLK_PERIOD, FS_PER_NS)); } static uint64_t ns_to_ticks(uint64_t value) { return (muldiv64(value, FS_PER_NS, HPET_CLK_PERIOD)); } static uint64_t hpet_fixup_reg(uint64_t new, uint64_t old, uint64_t mask) { new &= mask; new |= old & ~mask; return new; } static int activating_bit(uint64_t old, uint64_t new, uint64_t mask) { return (!(old & mask) && (new & mask)); } static int deactivating_bit(uint64_t old, uint64_t new, uint64_t mask) { return ((old & mask) && !(new & mask)); } static uint64_t hpet_get_ticks(void) { uint64_t ticks; ticks = ns_to_ticks(qemu_get_clock(vm_clock) + hpet_statep->hpet_offset); return ticks; } /* * calculate diff between comparator value and current ticks */ static inline uint64_t hpet_calculate_diff(HPETTimer *t, uint64_t current) { if (t->config & HPET_TN_32BIT) { uint32_t diff, cmp; cmp = (uint32_t)t->cmp; diff = cmp - (uint32_t)current; diff = (int32_t)diff > 0 ? diff : (uint32_t)0; return (uint64_t)diff; } else { uint64_t diff, cmp; cmp = t->cmp; diff = cmp - current; diff = (int64_t)diff > 0 ? diff : (uint64_t)0; return diff; } } static void update_irq(struct HPETTimer *timer) { qemu_irq irq; int route; if (timer->tn <= 1 && hpet_in_legacy_mode()) { /* if LegacyReplacementRoute bit is set, HPET specification requires * timer0 be routed to IRQ0 in NON-APIC or IRQ2 in the I/O APIC, * timer1 be routed to IRQ8 in NON-APIC or IRQ8 in the I/O APIC. */ if (timer->tn == 0) { irq=timer->state->irqs[0]; } else irq=timer->state->irqs[8]; } else { route=timer_int_route(timer); irq=timer->state->irqs[route]; } if (timer_enabled(timer) && hpet_enabled()) { qemu_irq_pulse(irq); } } static void hpet_pre_save(void *opaque) { HPETState *s = opaque; /* save current counter value */ s->hpet_counter = hpet_get_ticks(); } static int hpet_post_load(void *opaque, int version_id) { HPETState *s = opaque; /* Recalculate the offset between the main counter and guest time */ s->hpet_offset = ticks_to_ns(s->hpet_counter) - qemu_get_clock(vm_clock); return 0; } static const VMStateDescription vmstate_hpet_timer = { .name = "hpet_timer", .version_id = 1, .minimum_version_id = 1, .minimum_version_id_old = 1, .fields = (VMStateField []) { VMSTATE_UINT8(tn, HPETTimer), VMSTATE_UINT64(config, HPETTimer), VMSTATE_UINT64(cmp, HPETTimer), VMSTATE_UINT64(fsb, HPETTimer), VMSTATE_UINT64(period, HPETTimer), VMSTATE_UINT8(wrap_flag, HPETTimer), VMSTATE_TIMER(qemu_timer, HPETTimer), VMSTATE_END_OF_LIST() } }; static const VMStateDescription vmstate_hpet = { .name = "hpet", .version_id = 1, .minimum_version_id = 1, .minimum_version_id_old = 1, .pre_save = hpet_pre_save, .post_load = hpet_post_load, .fields = (VMStateField []) { VMSTATE_UINT64(config, HPETState), VMSTATE_UINT64(isr, HPETState), VMSTATE_UINT64(hpet_counter, HPETState), VMSTATE_STRUCT_ARRAY(timer, HPETState, HPET_NUM_TIMERS, 0, vmstate_hpet_timer, HPETTimer), VMSTATE_END_OF_LIST() } }; /* * timer expiration callback */ static void hpet_timer(void *opaque) { HPETTimer *t = (HPETTimer*)opaque; uint64_t diff; uint64_t period = t->period; uint64_t cur_tick = hpet_get_ticks(); if (timer_is_periodic(t) && period != 0) { if (t->config & HPET_TN_32BIT) { while (hpet_time_after(cur_tick, t->cmp)) t->cmp = (uint32_t)(t->cmp + t->period); } else while (hpet_time_after64(cur_tick, t->cmp)) t->cmp += period; diff = hpet_calculate_diff(t, cur_tick); qemu_mod_timer(t->qemu_timer, qemu_get_clock(vm_clock) + (int64_t)ticks_to_ns(diff)); } else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) { if (t->wrap_flag) { diff = hpet_calculate_diff(t, cur_tick); qemu_mod_timer(t->qemu_timer, qemu_get_clock(vm_clock) + (int64_t)ticks_to_ns(diff)); t->wrap_flag = 0; } } update_irq(t); } static void hpet_set_timer(HPETTimer *t) { uint64_t diff; uint32_t wrap_diff; /* how many ticks until we wrap? */ uint64_t cur_tick = hpet_get_ticks(); /* whenever new timer is being set up, make sure wrap_flag is 0 */ t->wrap_flag = 0; diff = hpet_calculate_diff(t, cur_tick); /* hpet spec says in one-shot 32-bit mode, generate an interrupt when * counter wraps in addition to an interrupt with comparator match. */ if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) { wrap_diff = 0xffffffff - (uint32_t)cur_tick; if (wrap_diff < (uint32_t)diff) { diff = wrap_diff; t->wrap_flag = 1; } } qemu_mod_timer(t->qemu_timer, qemu_get_clock(vm_clock) + (int64_t)ticks_to_ns(diff)); } static void hpet_del_timer(HPETTimer *t) { qemu_del_timer(t->qemu_timer); } #ifdef HPET_DEBUG static uint32_t hpet_ram_readb(void *opaque, target_phys_addr_t addr) { printf("qemu: hpet_read b at %" PRIx64 "\n", addr); return 0; } static uint32_t hpet_ram_readw(void *opaque, target_phys_addr_t addr) { printf("qemu: hpet_read w at %" PRIx64 "\n", addr); return 0; } #endif static uint32_t hpet_ram_readl(void *opaque, target_phys_addr_t addr) { HPETState *s = (HPETState *)opaque; uint64_t cur_tick, index; DPRINTF("qemu: Enter hpet_ram_readl at %" PRIx64 "\n", addr); index = addr; /*address range of all TN regs*/ if (index >= 0x100 && index <= 0x3ff) { uint8_t timer_id = (addr - 0x100) / 0x20; if (timer_id > HPET_NUM_TIMERS - 1) { printf("qemu: timer id out of range\n"); return 0; } HPETTimer *timer = &s->timer[timer_id]; switch ((addr - 0x100) % 0x20) { case HPET_TN_CFG: return timer->config; case HPET_TN_CFG + 4: // Interrupt capabilities return timer->config >> 32; case HPET_TN_CMP: // comparator register return timer->cmp; case HPET_TN_CMP + 4: return timer->cmp >> 32; case HPET_TN_ROUTE: return timer->fsb >> 32; default: DPRINTF("qemu: invalid hpet_ram_readl\n"); break; } } else { switch (index) { case HPET_ID: return s->capability; case HPET_PERIOD: return s->capability >> 32; case HPET_CFG: return s->config; case HPET_CFG + 4: DPRINTF("qemu: invalid HPET_CFG + 4 hpet_ram_readl \n"); return 0; case HPET_COUNTER: if (hpet_enabled()) cur_tick = hpet_get_ticks(); else cur_tick = s->hpet_counter; DPRINTF("qemu: reading counter = %" PRIx64 "\n", cur_tick); return cur_tick; case HPET_COUNTER + 4: if (hpet_enabled()) cur_tick = hpet_get_ticks(); else cur_tick = s->hpet_counter; DPRINTF("qemu: reading counter + 4 = %" PRIx64 "\n", cur_tick); return cur_tick >> 32; case HPET_STATUS: return s->isr; default: DPRINTF("qemu: invalid hpet_ram_readl\n"); break; } } return 0; } #ifdef HPET_DEBUG static void hpet_ram_writeb(void *opaque, target_phys_addr_t addr, uint32_t value) { printf("qemu: invalid hpet_write b at %" PRIx64 " = %#x\n", addr, value); } static void hpet_ram_writew(void *opaque, target_phys_addr_t addr, uint32_t value) { printf("qemu: invalid hpet_write w at %" PRIx64 " = %#x\n", addr, value); } #endif static void hpet_ram_writel(void *opaque, target_phys_addr_t addr, uint32_t value) { int i; HPETState *s = (HPETState *)opaque; uint64_t old_val, new_val, val, index; DPRINTF("qemu: Enter hpet_ram_writel at %" PRIx64 " = %#x\n", addr, value); index = addr; old_val = hpet_ram_readl(opaque, addr); new_val = value; /*address range of all TN regs*/ if (index >= 0x100 && index <= 0x3ff) { uint8_t timer_id = (addr - 0x100) / 0x20; DPRINTF("qemu: hpet_ram_writel timer_id = %#x \n", timer_id); HPETTimer *timer = &s->timer[timer_id]; switch ((addr - 0x100) % 0x20) { case HPET_TN_CFG: DPRINTF("qemu: hpet_ram_writel HPET_TN_CFG\n"); val = hpet_fixup_reg(new_val, old_val, HPET_TN_CFG_WRITE_MASK); timer->config = (timer->config & 0xffffffff00000000ULL) | val; if (new_val & HPET_TN_32BIT) { timer->cmp = (uint32_t)timer->cmp; timer->period = (uint32_t)timer->period; } if (new_val & HPET_TIMER_TYPE_LEVEL) { printf("qemu: level-triggered hpet not supported\n"); exit (-1); } break; case HPET_TN_CFG + 4: // Interrupt capabilities DPRINTF("qemu: invalid HPET_TN_CFG+4 write\n"); break; case HPET_TN_CMP: // comparator register DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP \n"); if (timer->config & HPET_TN_32BIT) new_val = (uint32_t)new_val; if (!timer_is_periodic(timer) || (timer->config & HPET_TN_SETVAL)) timer->cmp = (timer->cmp & 0xffffffff00000000ULL) | new_val; if (timer_is_periodic(timer)) { /* * FIXME: Clamp period to reasonable min value? * Clamp period to reasonable max value */ new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1; timer->period = (timer->period & 0xffffffff00000000ULL) | new_val; } timer->config &= ~HPET_TN_SETVAL; if (hpet_enabled()) hpet_set_timer(timer); break; case HPET_TN_CMP + 4: // comparator register high order DPRINTF("qemu: hpet_ram_writel HPET_TN_CMP + 4\n"); if (!timer_is_periodic(timer) || (timer->config & HPET_TN_SETVAL)) timer->cmp = (timer->cmp & 0xffffffffULL) | new_val << 32; else { /* * FIXME: Clamp period to reasonable min value? * Clamp period to reasonable max value */ new_val &= (timer->config & HPET_TN_32BIT ? ~0u : ~0ull) >> 1; timer->period = (timer->period & 0xffffffffULL) | new_val << 32; } timer->config &= ~HPET_TN_SETVAL; if (hpet_enabled()) hpet_set_timer(timer); break; case HPET_TN_ROUTE + 4: DPRINTF("qemu: hpet_ram_writel HPET_TN_ROUTE + 4\n"); break; default: DPRINTF("qemu: invalid hpet_ram_writel\n"); break; } return; } else { switch (index) { case HPET_ID: return; case HPET_CFG: val = hpet_fixup_reg(new_val, old_val, HPET_CFG_WRITE_MASK); s->config = (s->config & 0xffffffff00000000ULL) | val; if (activating_bit(old_val, new_val, HPET_CFG_ENABLE)) { /* Enable main counter and interrupt generation. */ s->hpet_offset = ticks_to_ns(s->hpet_counter) - qemu_get_clock(vm_clock); for (i = 0; i < HPET_NUM_TIMERS; i++) if ((&s->timer[i])->cmp != ~0ULL) hpet_set_timer(&s->timer[i]); } else if (deactivating_bit(old_val, new_val, HPET_CFG_ENABLE)) { /* Halt main counter and disable interrupt generation. */ s->hpet_counter = hpet_get_ticks(); for (i = 0; i < HPET_NUM_TIMERS; i++) hpet_del_timer(&s->timer[i]); } /* i8254 and RTC are disabled when HPET is in legacy mode */ if (activating_bit(old_val, new_val, HPET_CFG_LEGACY)) { hpet_pit_disable(); } else if (deactivating_bit(old_val, new_val, HPET_CFG_LEGACY)) { hpet_pit_enable(); } break; case HPET_CFG + 4: DPRINTF("qemu: invalid HPET_CFG+4 write \n"); break; case HPET_STATUS: /* FIXME: need to handle level-triggered interrupts */ break; case HPET_COUNTER: if (hpet_enabled()) printf("qemu: Writing counter while HPET enabled!\n"); s->hpet_counter = (s->hpet_counter & 0xffffffff00000000ULL) | value; DPRINTF("qemu: HPET counter written. ctr = %#x -> %" PRIx64 "\n", value, s->hpet_counter); break; case HPET_COUNTER + 4: if (hpet_enabled()) printf("qemu: Writing counter while HPET enabled!\n"); s->hpet_counter = (s->hpet_counter & 0xffffffffULL) | (((uint64_t)value) << 32); DPRINTF("qemu: HPET counter + 4 written. ctr = %#x -> %" PRIx64 "\n", value, s->hpet_counter); break; default: DPRINTF("qemu: invalid hpet_ram_writel\n"); break; } } } static CPUReadMemoryFunc * const hpet_ram_read[] = { #ifdef HPET_DEBUG hpet_ram_readb, hpet_ram_readw, #else NULL, NULL, #endif hpet_ram_readl, }; static CPUWriteMemoryFunc * const hpet_ram_write[] = { #ifdef HPET_DEBUG hpet_ram_writeb, hpet_ram_writew, #else NULL, NULL, #endif hpet_ram_writel, }; static void hpet_reset(void *opaque) { HPETState *s = opaque; int i; static int count = 0; for (i=0; i<HPET_NUM_TIMERS; i++) { HPETTimer *timer = &s->timer[i]; hpet_del_timer(timer); timer->tn = i; timer->cmp = ~0ULL; timer->config = HPET_TN_PERIODIC_CAP | HPET_TN_SIZE_CAP; /* advertise availability of ioapic inti2 */ timer->config |= 0x00000004ULL << 32; timer->state = s; timer->period = 0ULL; timer->wrap_flag = 0; } s->hpet_counter = 0ULL; s->hpet_offset = 0ULL; /* 64-bit main counter; 3 timers supported; LegacyReplacementRoute. */ s->capability = 0x8086a201ULL; s->capability |= ((HPET_CLK_PERIOD) << 32); s->config = 0ULL; if (count > 0) /* we don't enable pit when hpet_reset is first called (by hpet_init) * because hpet is taking over for pit here. On subsequent invocations, * hpet_reset is called due to system reset. At this point control must * be returned to pit until SW reenables hpet. */ hpet_pit_enable(); count = 1; } void hpet_init(qemu_irq *irq) { int i, iomemtype; HPETState *s; DPRINTF ("hpet_init\n"); s = qemu_mallocz(sizeof(HPETState)); hpet_statep = s; s->irqs = irq; for (i=0; i<HPET_NUM_TIMERS; i++) { HPETTimer *timer = &s->timer[i]; timer->qemu_timer = qemu_new_timer(vm_clock, hpet_timer, timer); } vmstate_register(-1, &vmstate_hpet, s); qemu_register_reset(hpet_reset, s); /* HPET Area */ iomemtype = cpu_register_io_memory(hpet_ram_read, hpet_ram_write, s); cpu_register_physical_memory(HPET_BASE, 0x400, iomemtype); }